Crystallization and preliminary X-ray studies of human recombinant interleukin-2

• Published in: The Journal of biological chemistry 1987-04, Vol.262 (10), p.4766-4769
• Main Authors: Sano, C., Ishikawa, K., Nagashima, N., Tsuji, T., Kawakita, T., Fukuhara, K., Mitsui, Y., Iitaka, Y.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cloning, Molecular; Crystalline structure; Crystallization; Fundamental and applied biological sciences. Psychology; Humans; Interleukin-2 - genetics; Interleukin-2 - isolation & purification; Molecular biophysics; Structure in molecular biology; X-Ray Diffraction
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)61261-X

Two different forms of crystals (potentially) suitable for x-ray structure analysis were obtained for recombinant human interleukin-2 (IL-2) using ammonium sulfate as a precipitant in the pH range of 6.3-7.3 (in the case of hexagonal bipyramidal crystals) and 4.5-5.5 (in the case of plate crystals). The hexagonal bipyramidal crystal belongs to a hexagonal space group P6(2)22 or P6(4)22 with a = b = 105.8 A and c = 122.2 A. The crystal diffracts up to 3.4 A resolution and contains 2 or 3 IL-2 molecules in an asymmetric unit. The plate crystal belongs to an orthorhombic space group P2(1)2(1)2 with a = 47.9 A, b = 79.6 A, and c = 31.9 A. The crystal diffracts up to 2.5 A resolution and contains only 1 IL-2 molecule in an asymmetric unit. These facts reconfirmed crystallographically the high homogeneity of the present preparation of human recombinant IL-2.